President Bush and Gen. David Petraeus had two main goals in sending 30,000 more troops to Iraq last year: reduce the horrific violence and give Sunnis, Kurds and Shiites breathing room to resolve their differences and create an effective national government.

Today, as Petraeus appears before Congress, he can point to a mission somewhat accomplished. Deaths are down, both among U.S. soldiers and Iraqi civilians. But "political progress is so slow, halting and superficial … that the U.S. is no closer to being able to leave Iraq than it was a year ago.''

That's from a new report by the U.S. Institute of Peace, a nonpartisan body created by Congress that brought together experts to discuss U.S. policy on Iraq. As glum as it is about the country's political progress, it also shows a troubling lack of consensus about where that policy should go from here.

Would threatening a quick troop withdrawal force Iraq's political leaders to get their act together? Would withdrawing U.S. troops plunge the country into civil war and even genocide?

Would it be better to forget about a strong central government and concentrate on strengthening local and provincial governments? Is it risky to keep forming alliances with tribes and sects that could one day turn against the United States, as the Taliban did in Afghanistan?

"What strikes me from the report is how really difficult the decisionmaking is going to be on this,'' says co-author Daniel Serwer, a former foreign service officer who has visited Iraq twice in recent months.

"For me personally, having our military tied down in Iraq almost completely for five years and with the prospect of another five is a big problem. Almost anybody who's elected president will in January 2009 be focused on how do we reduce our commitment in Iraq.''

Experts convened by the peace institute agree that U.S. policy should aim at keeping Iraq a single country and prevent it from becoming a haven for international terrorists or falling further under Iran's sway. Other policy goals should include improving regional stability and restoring U.S. credibility worldwide.

Beyond that the experts are torn over the best way to spur political progress, without which "the U.S. risks getting bogged down in Iraq for a long time to come,'' the report warns.

Although Iraq now has a constitution and a democratically elected Parliament, the central government in Baghdad remains weak and torn by disagreements among Sunnis, Shiites and Kurds. That has prevented the passage of some critical legislation, including a law that was supposed to have been passed last year on the control of Iraq's oil wealth.

Iraq's army also remains less than a crack fighting force despite the billions of dollars the United States has spent arming and training it.

That became apparent last month when Prime Minister Nouri al-Maliki sent Iraqi soldiers into Basra to fight Shiite militias, including that of a political rival, the cleric Muqtada al-Sadr. Hundreds of soldiers deserted or refused to fight while the rest barely held their own against Sadr's Mahdi Army.

Given the self-interests of politicians in Baghdad and the limitations of the national army, "the U.S. may be better off directing its effort to the local level even more than it already has,'' the report says.

"Later on, after new, more locally oriented political parties emerge and take part in elections, the stage may be set for a real and lasting national political reconciliation.''

Even with a full and unconditional commitment from the Americans, it could take 10 years for Iraq to achieve lasting political stability, the report says. Minus such a commitment, experts agree the United States needs to find an alternate policy that will protect at least some vital U.S. interests. Two options:

• Make future U.S. support conditional on the Iraqi government passing an oil law, developing a professional nonsectarian army and holding provincial elections.

• Withdraw all U.S. forces from Iraq, but bolster American troop strength in other parts of the region and offer continued diplomatic and political support to the Iraqi government.

Any option, the experts agree, would have a better chance of success if Iraq's neighbors cooperated. In recent months, Syria appears to have restricted the number of foreign fighters entering Iraq while there have been fewer attacks on coalition forces attributable to weapons from Iran, the report says.

While there remains "no visible end'' to the U.S. commitment in Iraq, the report says, Petraeus may be able to tell Congress today that the situation is not as hopeless as it has often seemed.

"So far in Iraq, you would have been right for five solid years by predicting things would get worse,'' Serwer says.

"But it's like the stock market — some day it will turn around. Frankly, Iraqis are fed up with the fighting, and Iraqi politicians are acutely aware that the people of Iraq want this to stop. The question is: Can the deals be worked out that enable this to stop and will the neighbors also cooperate?''